1. Technical Field
This invention relates generally to electronic devices and in particular to a radio frequency signal splitter device.
2. State of the Art
Signal splitters are an electronic device that is used to divide an electronic input signal into two or more versions of the input signal. Signal splitters often accept a downstream input signal at an input port, and provide a reduced-power version of the input signal at two or more output ports. In the reverse direction, an upstream signal received at an output port is transmitted to the input port for continued upstream transmission. In general, there is intentionally high isolation (insertion loss) between the output ports of a signal splitter. This means that there is a high amount of attenuation in a transmission path extending from one splitter output port to another splitter output port.
High isolation (high insertion loss) between output ports is often a desirable feature in a signal splitter. There are applications, however, where it is desirable to transmit signals between output ports of a signal splitter with a minimum of attenuation. In particular it is desirable in some applications to provide a signal splitter that operates in at least two radio-frequency bands of operation, a first radio-frequency band and a second radio-frequency band. High isolation is desirable between splitter output ports in the first frequency band, but low isolation—less attenuation—is desired in the second frequency band. Lowering the isolation between output ports of a splitter has been implemented in some particular splitter devices, but there are drawbacks, including reduced splitter performance outside the particular frequency band of interest, and isolation that is still too high within the particular frequency band of interest. Thus there is a need for an electronic splitter device that provides frequency dependent splitter performance, including high isolation between output ports in a first frequency band, and low isolation between output ports in a second frequency band, without compromising splitter performance in either the first or the second frequency bands.